short answer: don't.
long answer: The only thing he has worth farming for is union attack, and maybe some number of gammas (if you want to do the magnet warriors deck). The problem being that in general, there are no good ways to farm him, and the only ok way to farm him not only involves union attacks (defeating the purpose) but also requires 3 Gravity axe garls, which are from a set you do not want to be investing in.
Get the cards another way, or just play fast clear decks like cas against him and go for high repetition/low score games. CAs are probably ideal to prevent a feint plan trolling quick victories.

I haven't even bothered learning that stuff, because by and large most races don't allow major glitches. I've learned the minor stuff that is allowed (bomb jumps, dark room strats), although still haven't learned how to do silverless ganon yet.

yes.
actually shooting mechanics haven't changed much if at all in the past couple of decades. Part of the reason why Doom 1 and 2 still hold up well as shooters despite them being ancient is because fps games really haven't progressed far enough beyond them yet that they feel bad in comparison. I think I've played like 1 game in the past 15 years that made me go 'this game's shooting is a fucking blast', and that was doom 2016, which really wasn't even innovative so much as it was a port of what made doom 1 and 2 great.
Hell, there are still only 2 real models of inventory management in shooters, the halo 2 gun model and the doom 'everything you find' model. Fps games almost embody if it ain't broke don't fix it.

ME3 is by far the single biggest waste of potential i've ever seen in a game. It's like 'hey guys, remember that incredibly in-depth universe we build, with deep and fascinating characters? Lets completely fail to add anything to that in any way! Oh yeah, and those amazing characters? Aside from like 4, lets relegate them to stan lee -esque cameos that are literally so forgettable that if they died in a previous game we inserted a nameless character in their place and it changes nothing!. Oh, and you'll love all 3 of the new characters we introduced, who range from boring to boring! We hope you're happy with our high quality product'.
Don't even get me started on the ending bullshit, and I'm not even talking about the actual mechanics of the ending.
Don't get me wrong, it's hard to call ME3 a bad game, it's well put together gameplay wise (I mean, it's a more polished ME2, which while not exactly world shaking is strong enough), and is solid enough, but it absolutely punts the potential of ME 1+2.

HL2 is the best single player FPS ever made, bar none. Even as old as it is, it still hold up.
Mass Effect 2 is probably the best general single player shooter. Stellar game in all regards, story, gameplay, etc. ME1 was a fantastic world building game but had a lot of inexcusable flaws, and 3 was a very stagnant game, but 2 is just fantastic in all ways.
Never got into DOA or Witcher. Not for lack of trying, but just can't do it. Doesn't grab me.
Hot take: Skyrim is probably the most overrated game of all time. Like, it's not a bad game by any means, but it would not make any list of the best games in x category, aside from maybe graphics.

the obvious instance of speedster vs darhk was when darhk was doing the life sucky thing to oliver and barry raced in grabbed oliver and bailed. you'd think that if darhk could have stopped it he would have, especially since he was in physical contact with oliver, but he didn't.
p sure there's a couple of other instances of people getting the drop on darhk and coming closer (than if they hadn't at any rate) to if not outright getting him.

he is definitely not too overpowered compared to some of the big bads.
He was a horrible arrow big bad because he so hilarilously powercreeps literally every other villian combined, but in the grand scheme, he's not the big dog. He worked so well under thawne because thawne was literally the only person who was more powerful than he was (even at full power, this disregards the fact that darhk was just a league assassin in terms of powers during s2, as he didn't have the idol, but even at full power, darhk has always shown that his magic is gated by his reaction time, which means he's basically completely helpless against thawne.) Mallus just not existing makes it hard to tell if he's wielding that kind of power.

if wizards was going to axe mox, they'd have done it by now tbh. Affinity's presence on the format has remained more or less constant for the past...... god it's actually been a long time. Same with tron (tbf tron is better than it's been since the old days of straight g/r tron, but it's not exactly dominating the format).
The only real line of reasoning that might lead to affinity/tron getting hit boils down to 'we decided that there are too many sideboard check decks in the format. we're going to forcibly remove some', and I don't see that happening.

it's not supposed to be an unlimited format, that's legacy/vintage. It's supposed to be a relatively inexpensive eternal format.
the format when you get to do zany shit but without the price of paying for reserve list cards.